Discolouration of teeth can be caused by intrinsic or extrinsic factors.
Intrinsic discolouration occurs when there are changes that occur in the internal structure of the tooth.
Common causes of intrinsic discolouration presenting as grey lines or diffused grey colours:
1. Tetracycline staining
This commonly occurs amongst patients whose mothers took tetracycline (an antibiotic) during their pregnancy, or amongst patients who consumed tetracycline when they were children (typically 0 - 8 years in age). Tetracycline deposits stain the tooth structure throughout its growth.
2. Fluorosis
This happens when the water a patient regularly drinks has fluoride concentration that exceeds 1ppm. Excessive fluoride discolours teeth and this can appear as either frosty white patches or brown-black lines.
Extrinsic discolouration is caused by 'coloured' agents or chromogens which are deposited on the tooth surface.
Common causes of extrinsic discolouration presenting as grey lines or diffused grey colours:
1. Amalgam fillings
Patients who have Amalgam fillings can sometimes experience grey discolourations of the tooth, caused by the formation of silver sulfide that is deposited from filling material.
2. Dental materials
Some dental materials used in root canal treatment such as Ledermix can cause grey pigmentation of the tooth.
3. Dental Trauma
Patients who have experienced trauma to the teeth and damage of the pulp (where nerves and blood vessels are located), will see changes in tooth colour. This particular type of grey discolouration is more diffuse.
How to treat grey lines:
Speak with your dentist to determine the cause of the grey lines on your teeth and he/she can advise the most appropriate treatment options.
